A a polyvalent antigenic vaccine against clostridioses of animals, is known comprising antigens that are anacultures of Cl. perfringens types B, C, and D, Cl. oedematiens, Cl. septicum, Cl. tetani, and Cl. chauvoei, a mineral oil, a nonionic lipophilic emulsifying agent, and a nonionic hydrophilic emulsifying agent.
The presence of microbial cells in the vaccine produces a negative effect on detoxification and purification of the preparation to reduce its antigenic and immunogenic power, to increase the reactogenecity, and produces mainly antimicrobial immunity in the vaccinated animals.
A precipitated toxoid-vaccine is also known which contains a toxoid of Cl. perfringens type A, anacultures Cl. perfringens types B, C, and D, Cl. oedematiens, and Cl. septicum separated from the microbial mass. Alumina gel is used as an adsorbent. The activity of the toxoid of Cl. perfringens type A is measured in combining units per ml of the vaccine and is equal to 20 units.
The number of combining units characterizes the antigenic and immunogenic properties of the toxoid.
A combining unit is the quantity of the test toxoid (at various stages of its preparation), capable of combining with one antitoxic unit of specific serum. The specific activity of toxoids, expressed in combining units, is determined by the method proposed by G. P. Cherkas (1958) and I. M. Khaustova (1959).
The activity of each toxin of the starting cultures that are constituents of said vaccine is determined by the MLD (minimum lethal dose) and is, on an average, 400-1000 MLD in one ml of the vaccine (for albino mice).
The antigenic and immunogenic properties of the preparation are insufficiently strong, and it exhibits, mainly, antimicrobial immunity and a very weak antitoxic immunity against Clostridium perfringens types B, C, and D, Cl. oedematiens and Cl. septicum.
The vaccinated animals develop immunity very slowly, and it lasts for a short time: the immunity sharply weakens in 1-2 months, which involves repeated vaccinations with increased doses of the preparation.
A another vaccine, namely ditoxoid, is also known which is intended for specific prophylaxis of enterotoxemia of calves. The preparation includes toxoids of Clostridium perfringens types A and D, separated from the microbial mass, their antigenic activity being 100 combining units of each toxoid per ml, as well as a sorbent and a solvent. The sorbent used in the vaccine in alumina gel and the solvent, a physiological salt solution.
Said preparation cannot be used for treatment and prophylaxis of diseases caused by a combination of widely spread natural microorganisms of the genus Clostridium since it contains toxoids effective only against two causative agents.